The present disclosure relates generally to imaging members for electrophotography. Specifically, the disclosure teaches imaging members having a substrate, which can be a metal or metallized substrate in embodiments. In embodiments, the disclosure relates to imaging members having an undercoat layer having a polymer resin and a near infrared absorbing component that absorbs at an imaging member exposure wavelength and has a high molar extinction coefficient. In embodiments, the component is soluble in an undercoat layer solvent. In additional embodiments, one or more additional layers are disposed on the undercoat layer, and the additional layer or layers may include a charge-generating component and a charge-transport component.
In electrophotography, an electrophotographic substrate containing a photoconductive insulating layer on a conductive layer is imaged by first uniformly electrostatically charging a surface of the substrate. The substrate is then exposed to a pattern of activating electromagnetic radiation, such as, for example, light. The light or other electromagnetic radiation selectively dissipates the charge in illuminated areas of the photoconductive insulating layer while leaving behind an electrostatic latent image in non-illuminated areas of the photoconductive insulating layer. This electrostatic latent image is then developed to form a visible image by depositing finely divided electroscopic marking particles on the surface of the photoconductive insulating layer. The resulting visible image is then transferred from the electrophotographic substrate to a member, such as, for example, an intermediate transfer member or a print substrate, such as paper. This image developing process can be repeated as many times as necessary with reusable photoconductive insulating layers.
In electrophotography, an electrophotographic substrate containing a photoconductive insulating layer on a conductive layer is imaged by first uniformly electrostatically charging a surface of the substrate. The substrate is then exposed to a pattern of activating electromagnetic radiation, such as, for example, light. The light or other electromagnetic radiation selectively dissipates the charge in illuminated areas of the photoconductive insulating layer while leaving behind an electrostatic latent image in non-illuminated areas of the photoconductive insulating layer. This electrostatic latent image is then developed to form a visible image by depositing finely divided electroscopic marking particles on the surface of the photoconductive insulating layer. The resulting visible image is then transferred from the electrophotographic substrate to a member, such as, for example, an intermediate transfer member or a print substrate, such as paper. This image developing process can be repeated as many times as necessary with reusable photoconductive insulating layers.
Electrophotographic imaging members (i.e. photoreceptors) are well known. Electrophotographic imaging members are commonly used in electrophotographic (xerographic) processes having either a flexible belt or a rigid drum configuration. These electrophotographic imaging members sometimes comprise a photoconductive layer including a single layer or composite layers. These electrophotographic imaging members take many different forms. For example, layered photoresponsive imaging members are known in the art. U.S. Pat. No. 4,265,990, which is totally incorporated by reference herein, describes a layered photoreceptor having separate photogenerating and charge transport layers.
Photoconductive photoreceptors containing highly specialized component layers are also known. For example, a multilayered photoreceptor employed in electrophotographic imaging systems sometimes includes one or more of a substrate, an undercoating layer, an intermediate layer, an optional hole or charge blocking layer, a charge generating layer (including a photogenerating material in a binder) over an undercoating layer and/or a blocking layer, and a charge transport layer (including a charge transport material in a binder). Additional layers such as one or more overcoat layers are also sometimes included.
Photoconductive or photoresponsive imaging members are disclosed in the following U.S. Patents and U.S. Patent Applications, the disclosures of each of which are totally incorporated by reference herein, U.S. Pat. Nos. 4,265,990, 4,419,427, 4,429,029, 4,501,906, 4,555,463, 4,587,189, 4,709,029, 4,714,666, 4,937,164, 4,968,571, 5,019,473, 5,225,307, 5,336,577, 5,471,313, 5,473,064, 5,958,638, 5,645,965, 5,756,245, 5,797,064, 5,891,594, 6,051,351, 6,074,791, 6,194,110, 6,656,651, commonly assigned, co-pending U.S. Patent Application of John S. Chambers et al., Ser. No. 10/758,046, filed Jan. 16, 2004, entitled “Thick Intermediate and Undercoating Layers for Electrophotographic Imaging Members and Method for Making the Same” and commonly assigned, co-pending U.S. Patent Application of Jin Wu et al., Ser. No. 11/133,979, filed May 20, 2005, entitled “Imaging Member”. The appropriate components and process aspects of the each of the foregoing U.S. Patents may be selected for the present disclosure in embodiments thereof.
Current issues in xerography include the occurrence of ghost image effects on printed substrates. For example, known photoconductors are believed to be susceptible to carrier injection from the substrate into the photosensitive layer such that the charge on the surface of the photoconductor may be microscopically dissipated or decayed. This often results in production of a defective image. Another problem relates to the phenomenon referred to as transfer ghost, which is a transfer current induced ghosting defect on an image believed to be caused by internal charge migration and/or charge injection from the top surface or substrate.